Disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-)

Endpoint summary

Description of key information

Short term toxicity to aq. invertebrates:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, toxicity on daphnia magna was predicted for disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4). Based on the intoxication of test organism the EC50 value was estimated to be 126.59 mg/l when disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) exposed to daphnia magna for 48 hrs. Based on this value it can be concluded that the substance disodium [μ-[[7,7'-iminobis [4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate (2-) (6798-03-4) is considered to be nontoxic to aquatic environment and cannot classified as per the criteria mentioned in CLP regulation.    

Toxicity to aq. algae and cyanobacteria:

Based on the prediction done using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the eight closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4). Based on the growth rate inhibition of algae Pseudokirchneriella subcapitata by the chemical disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-), the EC50 was estimated to be 129.06 mg/l. Based on this value it can be concluded that the substance disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) is considered be nontoxic to aquatic environment and cannot be classified as per the criteria mentioned in CLP regulation.    

Additional information

Summarized result for the determination of nature of chemical disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) on the growth and other biological and physical activity of aquatic invertebrates, algae and cyanobacteria when chemical comes in contact with test organisms, by considering the data for target as well as structurally and functionally similar read across chemicals which are as follows: 

 

Short term toxicity to aq. invertebrates:

Based on the various predicted data for the target chemical and experimental data for structurally and functionally similar read across chemicals study have been reviewed to determine the toxic nature of target chemical disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) on the mobility of aquatic invertebrates. The studies are as mentioned below:  

 

In the first prediction for the target chemical disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the five closest read across substances, toxicity on daphnia magna was predicted for disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4). Based on the intoxication of test organism the EC50 value was estimated to be 126.59 mg/l when disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo]naphthalene-2-sulphonato]](6-)]]dicuprate(2-) exposed to daphnia magna for 48 hrs. Based on this value it can be concluded that the substance disodium [μ-[[7,7'-iminobis [4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate (2-) (6798-03-4) is considered to be nontoxic to aquatic environment and cannot classified as per the criteria mentioned in CLP regulation.    

 

First predicted study was supported by the second experimental weight of evidence study for the read across chemical Amaranth dye (915-67-3) from ABITEC report 2016. Determination of the inhibition of the mobility of daphnids was carried out with the substance 2,7-Naphthalenedisulfonic acid, 3-hydroxy- 4-[(4-sulfo-1-naphthalenyl), sodium salt; Amaranth dye according to OECD Guideline 202. The limit test was performed at 100 mg/l. Effects on immobilisation were observed for 48 hours. The effective concentration (EC8) for the test substance, 2,7-Naphthalenedisulfonic acid, 3-hydroxy-4- [(4-sulfo-1 -naphthalenyl), sodium salt (Amaranth dye), in Daphnia magna was determined to be 100 mg/L on the basis of mobility inhibition effects in a 48 hour study. This value indicates that the substance is likely to be non-hazardous to aquatic invertebrates and cannot be classified as toxic as per the CLP criteria.

 

The third study used for another functionally similar read across chemical from the experimental report (ABITEC report). Aim of the study was to assess the effect of chemical disodium 4-hydroxy-3-[(4-sulphonatonaphthyl)azo]naphthalenesulphonate on the mobility of daphnia magna. Test was conducted according to OECD Guideline 202. The stock solution 150 mg/l was prepared by dissolving dark red powder in reconstituted water. Test solutions of required concentration as were prepared by mixing the stock solution of the test sample with reconstituted test water. The test substance was tested at the 0, 0, 10, 45, 67.5, 100, 150 mg/l nominal concentration. Potassium dichromate (K2Cr2O7) were used as a reference positive control. Effects on immobilisation were observed for 48 hours by using nonlinear regression by the software Prism 4.0. After the exposure of chemical for 48 hrs 50 % immobility was observed. Based on the immobility of daphnia magna, the median effective concentration (EC50) for the test substance, disodium 4-hydroxy-3-[(4-sulphonatonaphthyl)azo]naphthalenesulphonate, in Daphnia magna was determined to be 203.2 mg/L for immobilisation effects. This value indicates that the substance is likely to be non-hazardous to aquatic invertebrates and cannot be classified as toxic as per the CLP criteria.

 

Similar classification was also observed for the most structurally similar read across chemical (2519-30-4) from the experimental test report 445/16. Aim of the study was to assess the effect of chemical tetrasodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo)) naphthalene-4,6-disulphonate (Brilliant black 1) on the mobility of daphnia magna. Test was conducted according to OECD Guideline 202. The stock solution 100 mg/l was prepared by dissolving red powder in reconstituted water. Test solutions of required concentration as were prepared by mixing the stock solution of the test sample with reconstituted test water. The test substance was tested at the 0, 5, 10, 20, 40, 80, 160 mg/l nominal concentration. Potassium dichromate (K2Cr2O7) were used as a reference positive control. Effects on immobilisation were observed for 48 hours by using nonlinear regression by the software Prism 4.0. After the exposure of chemical for 48 hrs 50 % immobility was observed. Based on the immobility of daphnia magna, the median effective concentration (EC50) for the test substance, tetrasodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)- 7-sulphonato-1-naphthylazo)) naphthalene-4,6-disulphonate (Brilliant black 1), in Daphnia magna was determined to be > 900 mg/L for immobilisation effects. This value indicates that the substance is likely to be non-hazardous to aquatic invertebrates and cannot be classified as toxic as per the CLP classification criteria.

 

Based on the predicted data for the target chemical (from OECD QSAR 2018) and for the read across chemical from experimental lab reports (ABITEC reports), it can be concluded that the substance disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) is considered to be not toxic to aquatic environment (aquatic invertebrates) and cannot be classified as toxic as per the criteria mentioned in CLP regulation.  

 

Toxicity to aq. algae and cyanobacteria:

Based on the various predicted data for the target chemical and experimental data for structurally and functionally similar read across chemicals study have been reviewed to determine the toxic nature of target chemical disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) on the growth of aquatic algae and cyanobacteria. The studies are as mentioned below:   

 

In the first prediction for the target chemical disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) using the OECD QSAR toolbox version 3.3 with log kow as the primary descriptor and considering the eight closest read across substances, toxicity on Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum) was predicted for disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4). Based on the growth rate inhibition of algae Pseudokirchneriella subcapitata by the chemical disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-), the EC50 was estimated to be 129.06 mg/l. Based on this value it can be concluded that the substance disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) is considered be nontoxic to aquatic environment and cannot be classified as per the criteria mentioned in CLP regulation.   

 

First predicted study was supported by the second experimental weight of evidence study for the read across chemical Amaranth dye (915-67-3) from ABITEC report 2016. Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance 2,7-Naphthalenedisulfonic acid, 3-hydroxy-4-[(4-sulfo-1-naphthalenyl), sodium salt (Amaranth dye) according to OECD Guideline 201. The stock solution (200 mg/L) was prepared by dissolving brown powder in OECD growth medium. Test solutions of required concentration were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture and tested at the concentrations 0, 12.5, 25, 50, 100, 200 mg/L. Effects on the growth rate of the organism were studied. The median effective concentration (ErC50) for the test substance, 2,7-Naphthalenedisulfonic acid, 3-hydroxy-4-[(4-sulfo-1- -naphthalenyl), sodium salt, in Desmodesmus subspicatus was determined to be 356.2 mg/L. This value indicates that the substance is likely to be non-hazardous to aquatic algae and cannot be classified as toxic as per the CLP criteria. 

 

The third study used for another functionally similar read across chemical from the experimental lab report (586/16 report). Freshwater algal growth inhibition test was carried out on Desmodesmus subspicatus with the substance Disodium 4-hydroxy- 3-[(4-sulphonatonaphthyl)azo]naphthalene-sulphonate according to OECD Guideline 201. The test substance was dissolved in OECD growth medium and tested at the concentrations 0, 2.6, 5.6, 12.0, 27.0, 59.0 and 130 mg/L. Effects on the growth rate of the organism were studied. The median effective concentration (ErC50) for the test substance, Disodium 4-hydroxy-3-[(4-sulphonatonaphthyl)azo] naphthalenesulphonate, in Desmodesmus subspicatus was determined to be 265.1 mg/L. Based on this ErC50 value and after comparing with CLP criteria for aquatic classification of the substance it is concluded that the substance Disodium 4-hydroxy-3-[(4-sulphonatonaphthyl) azo] naphthalenesulphonate does not exhibit toxicity to aquatic algae (Desmodesmus subspicatus).

 

Similar classification was also observed for the most structurally similar read across chemical (2519-30-4) from the experimental test report 444/16. Short term toxicity study of Tetrasodium 1-acetamido-2-hydroxy-3-(4-((4-sulphonatophenylazo)-7-sulphonato-1-naphthylazo))naphthalene-4,6-disulphonate (Brilliant black 1) to aquatic algae Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) was conducted for 72 hrs. Test was performed according to the 201 OECD guideline in a static system. The stock solution 100 mg/l was prepared by dissolving black powder in OECD growth medium. Test solutions of required concentration were prepared by mixing the stock solution of the test sample with OECD growth medium and inoculum culture and tested at the 0, 12, 20, 35, 60, 100 mg/l nominal concentrations. Effects on the growth rate of the organism were studied. Potassium dichromate (K2Cr2O7) were used as a reference positive control. Effects on growth rate were observed for 72 hours by using nonlinear regression by the software Prism 4.0. Based on the growth rate inhibition of test organism Desmodesmus subspicatus (previous name: Scenedesmus subspicatus) due to the chemical Tetrasodium 1-acetamido-2-hydroxy- 3-(4-((4-sulphonatophenylazo)- 7-sulphonato -1-naphthylazo)) naphthalene-4,6-disulphonate (Brilliant black 1), the effect concentration ErC50 was 76.8 mg/l. This value indicates that the substance is likely to be hazardous to aquatic algae and can be classified as aquatic chronic 3 as per the CLP criteria. But as the chemical was readily biodegradable in water so on that basis chemical was consider as nontoxic and can be consider to be not classified as per the CLP classification criteria.

 

Based on the predicted data for the target chemical (from OECD QSAR 2018) and for the read across chemical from experimental lab reports (ABITEC reports), it can be concluded that the substance disodium [μ-[[7,7'-iminobis[4-hydroxy-3-[[2-hydroxy-5-sulphamoylphenyl]azo] naphthalene-2-sulphonato]](6-)]]dicuprate(2-) (6798-03-4) is considered to be not toxic to aquatic environment (aquatic algae and cyanobacteria) and cannot be classified as toxic as per the criteria mentioned in CLP regulation.  

 

Thus based on the overall results including the toxicity to aquatic invertebrates and algae, it can be concluded that the chemical was nontoxic and can be consider to be not classified as per the CLP classification criteria.